Yeast translation elongation factor eEF3 promotes late stages of tRNA translocation.

Autor: Ranjan N; Department of Physical Biochemistry, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany., Pochopien AA; Gene Center, Department for Biochemistry and Center for integrated Protein Science Munich (CiPSM), University of Munich, Munich, Germany.; Institute for Biochemistry and Molecular Biology, University of Hamburg, Hamburg, Germany., Chih-Chien Wu C; Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA., Beckert B; Institute for Biochemistry and Molecular Biology, University of Hamburg, Hamburg, Germany., Blanchet S; Department of Physical Biochemistry, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany., Green R; Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA.; Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA., V Rodnina M; Department of Physical Biochemistry, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany., Wilson DN; Gene Center, Department for Biochemistry and Center for integrated Protein Science Munich (CiPSM), University of Munich, Munich, Germany.; Institute for Biochemistry and Molecular Biology, University of Hamburg, Hamburg, Germany.
Jazyk: angličtina
Zdroj: The EMBO journal [EMBO J] 2021 Mar 15; Vol. 40 (6), pp. e106449. Date of Electronic Publication: 2021 Feb 08.
DOI: 10.15252/embj.2020106449
Abstrakt: In addition to the conserved translation elongation factors eEF1A and eEF2, fungi require a third essential elongation factor, eEF3. While eEF3 has been implicated in tRNA binding and release at the ribosomal A and E sites, its exact mechanism of action is unclear. Here, we show that eEF3 acts at the mRNA-tRNA translocation step by promoting the dissociation of the tRNA from the E site, but independent of aminoacyl-tRNA recruitment to the A site. Depletion of eEF3 in vivo leads to a general slowdown in translation elongation due to accumulation of ribosomes with an occupied A site. Cryo-EM analysis of native eEF3-ribosome complexes shows that eEF3 facilitates late steps of translocation by favoring non-rotated ribosomal states, as well as by opening the L1 stalk to release the E-site tRNA. Additionally, our analysis provides structural insights into novel translation elongation states, enabling presentation of a revised yeast translation elongation cycle.
(© 2021 The Authors. Published under the terms of the CC BY 4.0 license.)
Databáze: MEDLINE
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